As the result of having some spare time yesterday I thought it would be appropriate to familiarize myself with the spare tire in my Z3 since I have had it for over 7 months now and didn't even know if the tire was there. Based on what I learned I assure you that you do not want to have a flat tire in a Z3 on some dark rainy night without having previously acquainted yourself with the gymnastics necessary to change a tire. I strongly suggest that all Z3 owners take a few minutes at their earliest convenience (like right away) to go thru the drill of changing the spare tire. Find yourself a nice quiet, flat out of the way space to park your Z3 and do the drill!

First, I looked in the owner's manual for instructions on changing the spare tire. About the only really useful information in the manual was a reference to the pictographs (pictograms?) glued to the inside of the trunk lid. They are the best source of information about what to do. Unfortunately, you will need someone with a flashlight to help you read them if the first time is at night. Following these instructions you learn that the spare tire is in a plastic tray that is supported by a frame of steel rods which in turn is suspended by two threaded bolts which enter into the trunk area thru two holes in the floorpan. These two bolts have nuts on the end of them that must be unscrewed in order to lower the frame assembly to the ground below the car. Having done that the tire in it's tray will slide out from under the car where the rest of the procedure is much closer to that normally expected in changing a tire.

Two interesting aspects of the procedure I learned were: 1. The air pressure in the spare tire can be checked from under the car by virtue of a short flexible rubber tube extending from the valve stem of the spare tire to the outside of the plastic tray covering the tire. 2. The white plastic garbage bag that came with the car is for you to put your dirty flat tire in after you have taken it off the car and before you put it in the trunk. Apparently BMW doen't want us to soil our lovely tunk space. Also, the instructions remind you that the tire and wheel off the car will not fit in the tray for the spacesaver spare.

After one has completed this important training experience I am sure that the first thing most of you will do is sit down and count the number of parts and weight that could be reduced if BMW would eliminate this crazy setup and replace the spare tire with a set of 4 "run flat" tires similiar to those being used on the 1997 Corvette. I would be willing to bet that an economic analysis of the savings in cost for parts and the reduction in operating costs due to the increase in gas mileage (from less weight) will show an overall reduced cost for "run flat" tires'. Try it folks and I am sure you will agree. Hopefully, BMW might require a few engineers to have to change a spare tire at the side of the road on a cold, dark rainy night and then I bet you we will see future Z3 models with 4 "run flat" tires.

Has anyone on the Digest had any tire changing experiences that you would like to share with us? If so, please let us know how you feel about the existing spare tire design and if you would like to see "run flat" tires on your next Z3!

Michelin, are you reading the Digest? Please make BMW an offer they can't refuse.

Fred Meloan
BMW CCA 86321 NCC
1989 E34 525iA 114,000 miles and going strong 1997 E36/7 Z3 2,000 miles and in need of "run flat" tires 1997 E39 540iA 3,000 miles and I'm already getting tired of the "chirp" Potomac, MD